We started recruitment for this case-control study in February, 2005. A pilot study has been completed in April 2006. The study will include at least 400 prostate cancer cases and at least 400 population-based controls. The participants will be an equal number of African-American and Caucasian males who reside in Baltimore City and surrounding areas. The cases are recruited at two Baltimore hospitals, the Veterans Affairs Medical Center and the University of Maryland Medical Center, over a 5-year period. Cases will have pathologically confirmed prostate cancer. The enrollment of controls began concurrently with case accrual, and recruitment will continue for 5 years. Controls are identified through the Department of Motor Vehicle database and will match cases by age, race, and residency. The study involves the administration of two questionnaires and the collection of blood from all study subjects. Fresh-frozen tumor specimens will be obtained from a subset of the cancer patients.